The Netherlands: In 2001, The Netherlands became the first country to legalize same-sex marriage. The country's first marriage was performed in Amsterdam's city hall on April 1, 2001.
Belgium: The country's gay-marriage law took effect June 1, 2003.
Spain: Same-sex marriage has been legal in Spain since July 3, 2005.
Canada: On July 20, 2005, Canada became the first country in the Americas to legalize same-sex marriage nationwide.
South Africa: Same-sex marriage became law in South Africa on Nov. 30, 2006, becoming the first and so far only African country to do so.
Norway: Norway's gay-marriage law went into effect on Jan. 1, 2009.
Sweden: Same-sex marriage became legal in Sweden on May 1, 2009.
Portugal: On June 5, 2010, same-sex marriage was legalized in Portugal.
Iceland: Iceland's same-sex marriage law took effect on June 27, 2010.
Argentina: Same-sex marriage in Argentina has been legal since July 22, 2010. Argentina was the first country in Latin America to allow same-sex marriage nationwide.
Denmark: On June 15, 2012, Denmark's gay-marriage law took effect. The country had been the first in the world to legally recognize same-sex couples through registered partnerships in 1989.
Uruguay: On April 10, Uruguayan lawmakers voted to legalize gay marriage, becoming the second South American country to do so.
New Zealand: On April 17, lawmakers in New Zealand passed a new law legalizing same-sex marriage. The bill will take effect in August.
France: France also legalized gay marriage in April with a law sponsored by the new Socialist President Francois Hollande.
Britain: After a bill to legalize same-sex marriage cleared Parliament, Queen Elizabeth II signed off to make it official on July 17, and gay wedding ceremonies are expected to start in 2014.